Chosen Solution
I have this exact issue, I have replaced all boards, Main video, power board, and T-conn, but i’m now stuck where this question left off. Black screen, with slow flashing white LED. My tv is the XBR65x850C, but having the exact same issue. Started with not powering on, replaced power board, nothing, replaced video board, LED flashed amber/green Tried to update via USB with latest firmware from sony website, Now still a black screen with slow flashing white LED. I’m hoping its not the panel now since I don’t have many options left. Any help on this would be great!
James Mckinney you really do not have a lot of options left. You mentioned a firmware update but did not tell us why or how it ended up. Also, you are certain that your replacement boards are all good. if you still have the old board, try the old main board and see what your led shows. Your TV should have a Smart Core Red LED that should have started to flash a pattern which would have identified which board is failing. It is possible that this is the panel itself but I would go through all the checks for the power situation as suggested by the sony fault finding flowcharts. Fault-finding-flowcharts.pdf Here are the steps to take for the software updates for the B-Board and the T-con board. See if these will work for you.
I just received a replacement main board and was running into the same problem. I think I just fixed the tv. I unplugged the tv, plugged in the usb with the firmware on it, and hooked up an ethernet cable to the tv. When I plugged in the tv the amber/green lights flashed for about 10 minutes, then it changed to a slow pulsing white light for another 10 minutes, then SONY appeared on the screen. It rebooted once, and then a message appeared telling me that the update was complete and to remove the usb.
Did you ever solve the problem? I am having the same issues. I’ve replaced the power board and main board, but still only get the white flashing LEDs from the remote. At a loss as to what to do next
